Point mutations including a novel Pro-197-Phe mutation confer cross-resistance to acetolactate synthase (ALS) inhibiting herbicides in Lactuca serriola in Australia.

Background: Control of prickly lettuce has become increasingly difficult for lentil growers in southern Australia because of widespread resistance to common herbicides, a lack of alternative herbicide options and the prolific production of highly mobile seed. This study aimed to quantify acetolactate synthase (ALS)-inhibiting herbicide resistance in the Mid North (MN) and Yorke Peninsula (YP) of South Australia, characterize the resistance mutations present and investigate population structure and gene flow in this species.

Results: Resistance was identified in all populations tested, with average survival of 92% to chlorsulfuron and 95% to imazamox + imazapyr.

Racism in Health Services for Adolescents: A Scoping Review.

Addressing racism within health systems and services is critical to addressing health vulnerabilities and promoting health equity for racialized populations. Currently, there is limited knowledge about the ways in which racism affects health services for adolescents. A scoping review was undertaken following the Joanna Briggs Institute Manual for Evidence Synthesis methodology and guided by the research questions: (1) What are the characteristics of the literature examining racism in health service use for adolescents? (2) What are the foci of the literature on systemic racism and health services for adolescents? A systematic literature search was conducted in April 2021 to identify all relevant published studies.

Inheritance and mechanism of glyphosate resistance in annual bluegrass (Poa annua L.).

Background: In initial screening, glyphosate was ineffective in controlling five Poa annua populations. These populations were tested for resistance, and studies undertaken to determine resistance mechanisms and inheritance pattern.

Results: Dose-response studies conducted at 16/12°C and 27/20°C on the five putative resistant populations showed low-level resistance (1.

Non-Mendelian inheritance of gene amplification-based resistance to glyphosate in Hordeum glaucum (barley grass) from South Australia.

Background: Hordeum glaucum Steud. is an important grass weed species in South Australia that has evolved resistance to glyphosate. This study investigated the mode of inheritance of glyphosate resistance in this species.

Stability of EPSPS gene copy number in Hordeum glaucum Steud (barley grass) in the presence and absence of glyphosate selection.

Background: Gene amplification has been shown to provide resistance to glyphosate in several weed species, including Hordeum glaucum populations in South Australia. The stability of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene copies in resistant populations in the presence or absence of glyphosate selection has not been determined.

Results: Applying glyphosate to a cloned plant resulted in an increase in resistance and EPSPS copy number in the progeny of that plant compared to the untreated clone.

Agricultural Weed Assessment Calculator: An Australian Evaluation.

Weed risk assessment systems are used to estimate the potential weediness or invasiveness of introduced species in non-agricultural habitats. However, an equivalent system has not been developed for weed species that occur in agronomic cropland. Therefore, the Agricultural Weed Assessment Calculator (AWAC) was developed to quantify the present and potential future adverse impact of a weed species on crop production and profitability (threat analysis), thereby informing or directing research, development, and extension (RDE) investments or activities.

Different Post-Sowing Nitrogen Management Approaches Required to Improve Nitrogen and Water Use Efficiency of Canola and Mustard.

Strategic use of nitrogen (N) may improve N use efficiency, but there is limited information on the influence of N supply at crucial growth stages on N accumulation, water use, and water use efficiency of canola and mustard. In this study, we hypothesize that genetic variation among canola and mustard can alter the response of timing and rate of post-sowing N application at targeted phenological growth stages by improving N and water use and their efficiencies. Field experiments were conducted in South Australia during two growing seasons with contrasting water availabilities.

EPSPS gene amplification confers resistance to glyphosate resistant populations of Hordeum glaucum Stued (northern barley grass) in South Australia.

Background: Glyphosate failed to control two populations of Hordeum glaucum (northern barley grass) along a fence line and around stockyards near Arthurton on the Yorke Peninsula, South Australia after more than a decade of regular use of glyphosate. These were investigated to confirm resistance and to determine resistance mechanisms.

Results: Dose-response experiments confirmed resistance of these populations to glyphosate with resistance levels of 2.

No apparent fitness costs associated with phytoene desaturase mutations conferred resistance to diflufenican and picolinafen in oriental mustard (Sisymbrium orientale L.).

Two mutations Leu498 and Glu425 in the PDS gene were identified as the main cause conferring resistance to diflufenican and picolinafen in two oriental mustard populations P3 and P40. As mutations are suspected to affect fitness, this study was designed to test this hypothesis using the F of two crosses P3.2 (P3♂ × S♀) and P40.

Cross-resistance to diflufenican and picolinafen and its inheritance in oriental mustard (Sisymbrium orientale L.).

Background: An oriental mustard population (P40) was identified as resistant to diflufenican by screening at the field rate. As diflufenican and picolinafen both target phytoene desaturase (PDS), cross-resistance to picolinafen was suspected. The mechanism of resistance and its inheritance to diflufenican and picolinafen were investigated.

The mechanism of diflufenican resistance and its inheritance in oriental mustard (Sisymbrium orientale L.) from Australia.

Background: An oriental mustard population (P3) collected near Quambatook, Victoria was identified as being resistant to diflufenican by screening with the field rate (200 g a.i. ha ) of the herbicide.

Reduced translocation in 2,4-D-resistant oriental mustard populations (Sisymbrium orientale L.) from Australia.

Background: Two oriental mustard populations (P2 and P13) collected from Port Broughton, South Australia were identified as resistant to 2,4-D. The level of resistance, mechanism and the mode of inheritance for 2,4-D resistance in these populations were investigated.

Results: Populations P2 and P13 were confirmed to be resistant to 2,4-D at the field rate (600 g a.

EPSPS gene amplification conferring resistance to glyphosate in windmill grass (Chloris truncata) in Australia.

Background: Five glyphosate-resistant populations of Chloris truncata originally collected from New South Wales were compared with one susceptible (S) population from South Australia to confirm glyphosate resistance and elucidate possible mechanisms of resistance.

Results: Based on the amounts of glyphosate required to kill 50% of treated plants (LD ), glyphosate resistance (GR) was confirmed in five populations of C. truncata (A536, A528, T27, A534 and A535.

Target-site mutations conferring resistance to glyphosate in feathertop Rhodes grass (Chloris virgata) populations in Australia.

Background: Chloris virgata is a warm-season, C , annual grass weed affecting field crops in northern Australia that has become an emerging weed in southern Australia. Four populations with suspected resistance to glyphosate were collected in South Australia, Queensland and New South Wales, Australia, and compared with one susceptible (S) population to confirm glyphosate resistance and elucidate possible mechanisms of resistance.

Results: Based on the rate of glyphosate required to kill 50% of treated plants (LD ), glyphosate resistance (GR) was confirmed in four populations of C.

Basis of ACCase and ALS inhibitor resistance in Hordeum glaucum Steud.

Background: Acetyl coenzyme-A carboxylase (ACCase) and/or acetolactate synthase (ALS) inhibitor resistance has been identified by herbicide resistance screening in eight populations obtained from cropping regions of South Australia. This study aimed to quantify the level of resistance and characterise the molecular basis of resistance to ACCase and ALS inhibitors in these H. glaucum populations.

Inheritance of evolved clethodim resistance in Lolium rigidum populations from Australia.

Background: In Australia, the extensive use of clethodim for the control of Lolium rigidum has resulted in the evolution of many clethodim-resistant L. rigidum populations. Five clethodim-resistant populations of L.

Women's experiences of factors that facilitate or inhibit gestational diabetes self-management.

Background: Gestational diabetes rates have increased dramatically in the past two decades and this pattern of increase appears to relate primarily to the obesity epidemic, older maternal age and migration from world areas of high GDM risk. Women from disadvantaged and migrant backgrounds are most at risk of developing and of mismanaging this condition. The aim of the study was to explore the factors that facilitated or inhibited gestational diabetes self-management among women in a socially deprived area.

Poor efficacy of herbicides in biochar-amended soils as affected by their chemistry and mode of action.

We evaluated wheat straw biochar produced at 450°C for its ability to influence bioavailability and persistence of two commonly used herbicides (atrazine and trifluralin) with different modes of action (photosynthesis versus root tip mitosis inhibitors) in two contrasting soils. The biochar was added to soils at 0%, 0.5% and 1.

Faster degradation of herbicidally-active enantiomer of imidazolinones in soils.

Imidazolinones are chiral herbicides, comprised of two enantiomers with differential herbicidal activity. In this study, the selective degradation of enantiomers of the three imidazolinone herbicides, imazapyr, imazethapyr and imazaquin, was determined in a variety of soils selected to cover a broad range of physico-chemical characteristics. The R(+) enantiomer of all three herbicides, which has greater herbicidal activity (up to eight times), was found to degrade faster than the less active S(-) enantiomer.

Improved extraction and clean-up of imidazolinone herbicides from soil solutions using different solid-phase sorbents.

Extraction and quantification of herbicide residues from soil are important in understanding the behaviour of persistent herbicides. This research investigated extraction and clean-up methods for imidazolinone herbicides from soil and soil amended with organic material. A series of solvent mixes, pH conditions and sorbents was tested.

Abiotic degradation (photodegradation and hydrolysis) of imidazolinone herbicides.

The abiotic degradation of the imidazolinone herbicides imazapyr, imazethapyr and imazaquin was investigated under controlled conditions. Hydrolysis, where it occurred, and photodegradation both followed first-order kinetics for all herbicides. There was no hydrolysis of any of the herbicides in buffer solutions at pH 3 or pH 7; however, slow hydrolysis occurred at pH 9.